The present invention relates to the field of raw cotton fiber and cotton seed processing. In the cotton processing industry, a saw is not a device for cutting into a material, but rather it is a device that has sharply pointed teeth for grasping the cotton fibers. The early “saw” gins used discs with sharp teeth around their peripheries that resembled circular saws, which probably is how the name, “saw” originated. Later, as seed cotton (cotton before ginning) was brought to the gins containing more and more extraneous matter, including the cotton hulls, machines were developed to extract this foreign matter, and these machines became known as “extractors”.
A common element in such extractor machines is a “channel saw.” Referring to FIGS. 1 to 4, the channel saw 11 is a thin metal strip formed into a right angle channel shape with sharp teeth 12 formed in rows 13 on the edges of the two equal legs of the channel shape. These outwardly opening channels are formed into arcs defined by the circumference of the cylinder 14 onto which the channel saws are to be peripherally mounted as shown in FIG. 2. Thus the channel runs perpendicular to the axis of rotation of the cylinder. These channel saws are about ½″ wide between the legs and are mounted about ½″ apart axially on the surface of the extractor machine cylinder. This spacing has proven to be efficient in extracting the large foreign matter from the seed cotton locks before ginning removing the fibers from the seeds.
Recently there have been developments in roller ginning that have increased the roller gin's ginning rate to near the rate of the saw gin. The roller ginning process has been proven to break fewer fibers than saw ginning, thus to make the fiber more valuable to the textile mills. Roller ginning has largely been confined to the relatively small extra long staple cotton varieties such as Pima because of the slow, more expensive roller ginning process. With the recent ginning rate increase of roller ginning, the better quality of roller ginned cotton should open the much larger upland cotton market to roller ginning. However, while the saw ginning process can adequately control the uniformity of the fiber remaining on the seeds, the roller ginning process must depend on “seed reclaimers” to retrieve the seeds with valuable fiber left on them from the seeds that are properly ginned and send the seed with valuable fiber back for further ginning. That is to say, the reclaimer removes un-ginned and partially-ginned seeds from a seed flow and directs them to a further lint removal process.
The increase in roller ginning rate, of course, must be accompanied by an increase in the rate of seed reclaimers to be successful. While the saw extractor technology of the prior art as described above shows promise for use in seed reclaimers, the efficiency of the current standard circumferentially extending extractor saws is not adequate. The seeds leaving the reclaimers that are to be sent to the properly ginned seed bin contain too many seeds with good fiber on them and the seeds that are to be returned for further ginning have too many already well ginned seeds. It should be understood that the output of a cotton gin stand has three components: the spinnable cotton fiber (lint), which is the most valuable component; the cotton seeds from which the fiber has been removed by the ginning process, which is salable at a lower rate than the fiber; and, the trash which was entrained with the seed cotton and has been extracted. When cotton seeds with ginnable fiber still on them are discharged with the well ginned seed component, the unginned fiber is sold at the rate of the seed, or worse, the fiber lowers the seed value for the sale to the dairy industry, thereby creating an inefficiency. Likewise, when the ginned seeds are discharged with the trash, the value of the seed is lost, yielding further inefficiency. It should be understood that cotton gin plants have many seed cotton cleaners (before the ginning process) that use spiked cleaning cylinders that convey seed cotton over spaced apart grid bars or coarse screens that are sized to allow optimum trash removal without allowing full seed locks to pass through the grids or screens. When partially or fully ginned seed pass over these grids or screens, there are often too few fibers on the seeds to prevent the seeds from falling out with the trash.
It is an object of the present invention to increase the processing rate of roller ginning of upland and pima cotton. It is a further object of the invention to more efficiently return cotton seeds having recoverable fiber attached thereto to the gin stand for further ginning. It is a concomitant object to eject well ginned seeds such that they do not return to the gin nor to the trash.
These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.